My sister has been driving my G35X. She says it been hard to start a few times. She had to just wait and keep trying until it starts sometimes up to 30 mins and when it does start it sputters then smooth's out. It hasn't done it when I'm driving it of course but she has called me when it does it. It has not generated any codes. Has anyone had this issue? I searched the forum but couldn't find the exact same issues. Please help.

 

Possibly a crank or cam sensor issue. Hard to say since you're relying on heresay and haven't experienced the problem yourself.

 

If it were a crank or cam sensor wouldn't it produce a code?

 

Not until it wasn't sending a signal, if it's sending the WRONG signal the ECM will try to use it.

 

Ok would you suggest changing both the sensors.

 

I know it's two cam sensors. I'm checking with infiniti now for the sensors.

 

If you have more than 100k miles on the engine I personally would just for preventative maintenance. When any of those sensors eventually fail it's one of the few things that will leave you stranded on the side of the highway.

1 crank sensor (CKP), 2 cam sensors (CMP) for a DE motor with 5AT transmission.
1 CKP, 4CMP (2 angled, 2 straight) for a rev-up DE motor in a 2005-2007 6MT equipped vehicle.
1CKP 4 CMP (all have 90 degree angle) for HR equipped 2007+ with 5AT transmission.

Only use OEM or Hitachi sensors, others are notorious for not working correctly or failing early.

However there could be MANY different things going wrong with your car and this is just throwing parts at it without actually finding the issue. I would also:
-Pull, inspect, replace spark plugs (replace if they have more than 60k miles on them).
-Have battery tested for proper current draw, clean up terminals thoroughly.
-Remove, inspect, clean PCV valve.

Also just to verify, the "hard starting" that she had, the engine still cranked normally yes? If the engine wasn't cranking AT ALL then that's a completely different issue and likely a bad starter.

 

Btw it's a 06 sedan auto and I have checked voltages levels and the I changed the plugs(from dealership) back in the summer. Car cranks fine no dragging or struggling to crank. I use to drag race mustangs for years and did most of the work myself so I do have some experience with cars. Just priced the sensors at the dealership hitachi brand $180 for the Crk sensor and $198 and $202 for the cam sensors. I can build a stock 302 for that price

 

Yeah don't actually buy them FROM the dealership. Get them from either a local supply house that carries hitachi sensors, or purchase on the internet. You can pick up the OEM Nissan ones on Amazon for a little under $100 apiece. The earlier revision sensors were all Hitachi's branded as Nissan so you can safely just buy the Hitachi's for $40 apiece.

 

Ok thanks for all the feedback. I was on amazon earlier looking. I drove it today no problems. Will be ordering sensors tonight and I'll let you know how it turns out.

 

OMG changed all three sensors yesterday and did not fix the issue

 

Ok try this next time you start the car, turn the key to ON, wait about 3 seconds for the fuel pump to finish priming, turn the key to OFF, wait one second, turn the key to ON again, wait about 3 seconds, then turn the key to START.

If this trick works you definitely have a fuel system problem, I've seen quite a few issues on various vehicles in the past where the fuel pump internal check valve fails and it bleeds back all the fuel pressure. A single cycle of the fuel pump on initial start isn't enough to bring the PSI back up to operating range but during cranking when the ECM turns the fuel pump back on it takes a little longer before the engine actually starts (there is a short window between key ON prime and cranking where the pump is turned off again, it turns on and stays on when the ECM finds the CKP sensor sending data back).

 

yes I've tried that because I know the pump comes on to prime the system before actually cranking. I lifted the back seat and had someone listen for the fuel pump as I turned the key maybe 4 or 5 times. I have a pattern now so it doesn't do it on a cold start like in the morning or after it sits for a long period after driving it only does after you drive and shut it off for a brief period (10 mins) then it will not start and when it does crank it stumbles really bad.

 

What do you think about the Mass airflow meter sensor?

 

Possibly, try cleaning the one you have thoroughly with MAF cleaner first.